Since the number of deaths increases and antimicrobial-resistant bacteria appear due to an infectious disease, an antimicrobial susceptibility test of infectious disease-causing bacteria is noticeably expedited. In the related art, the antimicrobial susceptibility test has been carried out based on a culture method. After a specimen such as blood, pharyngeal swab, and sputum is collected from an infectious patient, isolation culture is carried out overnight in order to obtain the infectious disease-causing bacteria as a single colony from the specimen in which indigenous bacteria coexist. Furthermore, after the bacteria forming the single colony are prepared to have a constant concentration, the bacteria are distributed to a container in which various types and various concentrations of antimicrobials/antibiotics are arranged, and antimicrobial susceptibility culture is carried out overnight. Then, after the culture, a result of the antimicrobial susceptibility test of the infectious disease-causing bacteria is obtained, based on the presence or absence of bacterial growth. In accordance with the received result, a proper antimicrobial is administered to a patient. Therefore, the proper antimicrobial is administered to the infectious patient three days later after the specimen is collected.
In contrast, as a method of quickly carrying out the antimicrobial susceptibility test, an ATP (Adenosine Triphosphate) bioluminescence method is noticeably used in which a change amount of ATP existing as an energy source inside the bacteria functions as an indicator of the bacteria growth. The ATP method is used in detecting the ATP existing as the energy source inside the bacteria by using firefly-derived enzyme luciferase. The luciferase oxidizes luciferin which serves as a substrate in the presence of ATP and Mg2+ inside the bacteria, and a luminescence amount generated at that time is proportional to an ATP amount. Accordingly, the bacteria growth can be evaluated, based on a change in the luminescence amount. For example, as a method of determining the number of bacteria by using the ATP method, PTL 1 discloses a technique in which the number of live bacteria and dead bacteria is obtained by counting the live bacteria through ATP measurement, counting total bacteria through a DNA method, and subtracting the live bacteria from the total bacteria.